Fluid pressure controlled holding device for a lift unit



2 Sheets-Sheet l INVENTOR ATTORNEY H. W. YEAGER, JR

HERBERT W.YEAGER,JR.

74 Fig,

Jan. 2, 196s FLUID PRESSURE CGNTROLLED HOLDING DEVICE FOR A LIFT UNITFiled June l, 1966 U Q UL 7/ Jan. 2, 1968 H. w. YEAGER, .1R

FLUID PRESSURE CONTROLLED HOLDING DEVICE FOR A LIFT UNIT 2 Sheets-Sheet2 Filed June l, 1966 Pfg. 3

Illnmmu Q lNvENToR HERBERT W..YEAGER,JR. BY

ATTORNEY United States Patent Ollce 3,361,469 Patented Jan. 2, 19683,361,469 FLUID PRESSURE CONTROLLED HOLDING DEVICE FOR A LIFT UNITHerbert W. Yeager, Jr., Philadelphia, Pa., assignor to The Budd Company,Philadelphia, Pa., a corporation of Pennsylvania Filed June 1, V1966,Ser. No. 554,526 2 Claims. (Cl. 294-64) ABSTRACT F THE DISCLOSURE Avacuum type holding apparatus for rapid attachment to an object andrelease therefrom upon command. The apparatus utilizes the ow of aliquid through a venturi for creating the vacuum for the attachingvacuum cup. A solenoid actuated valve blocks the normal ow of the liquidthrough the venturi and causes the liquid to flow into the vacuumportion of the venturi to destroy the vacuum and provide rapid releaseof the vacuum cup.

This invention relates to a lifting device and more particularly to aholding device for a lifting unit controlled by a uid under pressure.

There are commercially available vacuum actuated lift cups for holdingmaterial in a lirm grip for lifting or moving. However, in an automatedproduction line, the available commercial lifters do not react fas-tenough during initial contact for seizure and for fast release when thematerial has been moved.

An object of this invention is to provide a vacuum lift device operableby a pressurized uid for rapid activation and deactivation.

Another object of this invention is to provide a lift unit having aflexible cup operable by a pressurized fluid controlled by a solenoidand having sn-ap-in connections for rapid and easy replacement of afaulty unit.

A further object of this invention is to provide a resilient bumperadjacent the ilexible suction cup for cushioning the contact between thelift unit and the material Ito be moved for preven-ting localizeddeformation of the material to be moved.

Another object of this invention is to provide Ia lift system in whichpressurized fluid is used to create a vacuum for holding an object andalso is used to destroy the vacuum it created and exert pressure againstthe held object to repel it upon command.

These and other objects of this invention will be readily E seen byreference to the following specification and drawings wherein:

FIG. l is a front View of this novel invention prior to contact with thematerial to be moved and prior to activation of the lift unit.

FIG. 2 is a view in the direction of the arrows, substantial-ly alongthe line 2-2 of FIG. 1, showing the solenoid energized and the suctioncup in contact with the material to be moved.

FIG. 3 is a view of the lift unit situated for movement into themounting position on a lift arm of a transfer unit.

Referring now to the drawing, as best seen in FIG. 3, a lift unit islocated adjacent a lift arm 12 of a transfer unit (not shown). The liftarm 12 has coupling 14 connected to a source of fluid under pressure. Inthe preferred embodiment, pressurized air is used. A conventionalbayonet type removable air connector having the female portion 16secured in the lift ann 12 and connected to the pressurized air and themale portion 18 secured to the lift unit 10, is used for ease andrapidity of connecting the lift unit to the lift ann. A pair of femaleplugs 20 are secured in the lift arm 12 and connected to for cooperatingwith a pair of male plugs 22, 23 mounted in the lift unit 10.

Referring now to FIGS. 1 and 2, the lift unit 10 includes a body portion24 having a contact portion 26 secured thereto by a plural-ity of bolts28. One or more spacer plates 30 may be positioned between the bodyportion 24 and the contact head 26, as desired to accommodate thevarious heights of the unit for ldifferent applications. A resilientcontact ring 32 preferably of rubber or plastic is secured to the outeredge of the contact head 26. A commercially available vacuum cupassembly 34 is threadably secured in a threaded aperture 36 extendingthrough the Contact head 26. The vacuum cup assembly 34 includes aresilient cup portion 36 having an laperture 38 in t-ne center thereofconnecting the cup portion 36 with the hollow threaded portion 40.

A solenoid 42 is secured to the body portion 24 by screws 44 or othersuitable means. The electrical leads 46, 48 from the solenoid areconnected to the male plugs 22, 23 for actuation of the solenoid 42,upon command, when the lift unit 10 is mounted in operating position onthe lift arm 12.

A spring 50 biases the plunger 52 to the extended position shown in FIG.1 and is compressed by the action of the plunger 52 when the solenoid isactuated, as shown in FIG. 2.

The air passage 54, within the body 24, connects the pressurized airfrom connector 18, to a venturi sleeve 56, thread'ab'ly secured in atubular cavi-ty 58, of the body 24. The venturi sleeve 56, includes aninlet passage 60, a funnel shaped outlet passage 62, having its smallerend connected to said inlet and a reduced section 64, the reducedsection 64 cooperates with the walls of the cavity 58 to form an annularchamber 66, which is positioned about the juncture of the inlet passage60 and the outlet passage 62. A plurality of air passages or outlets 68extend from the juncture of the inlet and outlet passages to the chamber66.

An air passage 7G, extends from the chamber 66, to the hollow threadedportion 40, of the vacuum cup assembly 34, so that air may pass freelybetween the chamber 66, and the cup portion 36, of the vacuum cupassembly 34.

A stopper or plug 72 is secured to the plunger 52 of the solenoid 42,for movement into contact with the larger end of the outlet passage 62,when the solenoid is not energized, whereby the stopper 72 effectivelyblocks escape of pressurized air from the outlet. Upon energizing of thesolenoid 42, the plunger 52 overcomes the biasing action of spring 50and moves the stopper 72 from contact with outlet 62, thus allowing thepressurized air to escape therefrom.

In the operation of this device, with the lift unit secured to a liftarm, the solenoid 42 is energized by manual controls or automaticcontrols, such as a microswitch positioned for contact with the lift armduring its movement. Upon energizing of the solenoid, the plunger 52 andstopper 72 move to the position shown in FIG. 2. In this position, thepressurized air iiows from its source through the couplings 16, 18 andthe air passage 54 to the inlet passage 60 of the venturi sleeve 56. Asthe pressurized air passes through the venturi sleeve 56 from the inletpassage 60 through the outlet passage 62 to the atmosphere. The venturieffect of such passage creates a reduced pressure at the juncture at theinlet 60 and outlet 62 passages causing air to be drawn from the chamber66, through air passages 68, and a vacuum is created by such venturiaction in said chamber. The vacuum thus created extends through airpassage 70 to the vacuum cup assembly 34, and when the cup 36 contactsan object, such as the at plate 74, the reduced pressure within the cup36 and the atmospheric pressure on the plate 74, opposite the cupprovides a force differential acting on the plate for moving the plate74 into contact with the contact ring 22, in the position shown in FIG.2. A person skilled in the art can easily calculate the relative size ofair passages 68, inlet passage 610, outlet passage 62, and cup 34 forgiven conditions of air pressure and the Weight of the object to bemoved by the unit.

For rapid disconnect of cup 34, `from plate 74, the solenoid isdeenergized thus the plunger 52 and the stopper 72 are returned to theposition shown in FIG. l, at which time the escape of the pressurizedair from outlet 62 is blocked. The travel of the pressurized air thenwill flow from the inlet 66, through the air passages 68 to the chamber66, and through passage 76 to the vacuum cup assembly 34. As thepressurized air enters the cup 36, the vacuum therein is changed to apressurized area greater than atmospheric pressure and the plate 74 isforced by suchpressure away from ring 32, and cup 36, thus releasing andforcing the plate from the lift unit.

While but one embodiment of the present invention has been illustratedand explained, it is obvious various changes and modications may beincorporated without departing from the spirit and scope of theIfollowing claim.

What is claimed is:

1. A holding device for a lift unit including means for attaching saidlift unit to a movable arm -for movement therewith, a source of fluidunder pressure; a venturi sleeve having an inlet, a plurality ofoutlets, said inlet being connected to said pressurized uid source forpassage of said pressurized fluid therethrough; stopper means forcontrolling the ow of said pressurized fluid from said outlets uponcommand, flow of said pressurized uid through one of said outletscreating reduced pressure in said other outlet; a chamber connected tosaid other outlet, a fluid passage extending from said chamber, a vacuumcup assembly operably conneted to said uid passage, said vacuumcupassembly including a exible cup portioned for contacting a surface, saidcup portion having a reduced pressure of less than atmospheric pressuretherein when said presurized fluid passes through said one outlet -forusing atmospheric pressureto -urge and Vhold said vacuum cup assemblyand said surface into closer contact; resilient means for limitingmovement in one direction between said surface and said holding unit;actuating means for controlling movement of said stopper means out ofand into engagement with said one outlet, said pressurized tluid passingthrough said other outlets in said llexible cup portion when saidstopper means is in contact with said one outlet for creating a pressuretherein greater than atmospheric pressure whereby said surface isrepelled from said flexible cup and released from said holding device,said actuating means includes a solenoid having a plunger positionedtherein for reciprocal movement relative thereto when said solenoid isenergized, said stopper means secured to one end of said plunger formovement into and from engagement with said one outlet as said plungeris reciprocated, spring means biasing said plunger and said stoppermeans into engagement with said one outlet, energizing of said solenoidcausing movement of said plunger to overcome the biasing action of saidspring means and move said plunger means from engagement with said oneoutlet whereby said pressurized fluid flow therethrough, and means forenergizing said solenoid upon command.

2. The holding device claimed in claim 1 wherein said resilient meansfor limiting movement between said holding device and said held surfaceincludes a resilient material attached to said holding device and spacedfrom said vacuum cup a ldistance great enough to permit actuation ofsaid cup during application at a vacuum thereto.

References Cited UNITED STATES PATENTS 2,654,013 1/1954 Socke 29e-64X2,874,989 2/1959 Reynolds 294-64 3,039,623 6/1962 sehn 294-64 3,063,74611/1962 Oakes 294- 64V GERALD M. FORLENZA, Primary Examiner.

G. F. ABRAHAM, Assistant Examiner. n

